<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>新增语义化标签</title>

   <style>
       /* 这些语义化标签 需要转换块级元素 为了兼容浏览器 */
       header,nav,section,footer {
           display: block;
       }
       /* 内容头部，导航栏 */
       header,nav {
           width: 800px;
           height: 100px;
           border-radius: 15px;
           background-color: pink;
           margin: 10px auto;
       }
       /* section 定义某个区域的意思        */
       section {
          
           margin: 10px;
           width: 350px;
           height: 200px;
           background-color: skyblue;
       }
       div {
           clear: both;
       }
       /* 尾部的意思 */
       footer {
          
           width: 800px;
           height: 150px;
           background-color: purple;
           border-radius: 15px;
           margin:0 auto;
       }
   </style>
</head>
<body>
    <header>我是头部</header>
    <nav>我是导航栏</nav>
    <section>某个区域</section>
    <section>某个区域</section>
    <section>某个区域</section>

    <div></div>
    


    <footer>我是尾部区域</footer>
</body>
</html>